Arrangement for passing a line in a load-free manner through a pressure frame of a fuselage of an aircraft or spacecraft

ABSTRACT

The present invention provides an arrangement for passing a line in a load-free manner through a pressure frame of a fuselage of an aircraft or spacecraft, including an opening penetrating the pressure frame, through which opening the line is passed, the line being mechanically decoupled from the pressure frame; and a flexible sealing device arranged outside the opening at least in portions, which sealing device is simultaneously operatively connected to the line and the pressure frame for the pressure-tight separation of a first side from a second side of the pressure frame. The present invention also provides a fuselage for an aircraft or spacecraft having an arrangement of this type and an aircraft or spacecraft having an arrangement of this type or having a fuselage of this type.

CROSS-REFERENCES TO RELATED APPLICATIONS

This application is a continuation of and claims priority toPCT/EP2012/052630 filed Feb. 15, 2012 which claims the benefit of andpriority to U.S. Provisional Application No. 61/444,448, filed Feb. 18,2011, and German patent application No. 10 2011 004 385.3, filed Feb.18, 2011, the entire disclosures of which are herein incorporated byreference.

FIELD OF THE INVENTION

The present invention relates to an arrangement for passing a line in aload-free manner through a pressure frame of a fuselage of an aircraftor spacecraft, a fuselage for an aircraft or spacecraft having anarrangement of this type and an aircraft or spacecraft having anarrangement of this type or having a fuselage of this type.

Although applicable to any aircraft or spacecraft, the present inventionwill be described in greater detail by way of example with reference toan aircraft.

BACKGROUND OF THE INVENTION

During the flight phase of the aircraft, an internal pressure is usuallyapplied to the passenger cabin thereof, which internal pressure is abovethe external atmospheric pressure. For this purpose, the passenger cabinmust be constructed in a pressure-tight manner. This is achieved inparticular by means of a pressure frame arranged in the tail region ofthe aircraft. The pressure frame separates, for example, the pressurisedpassenger cabin from an unpressurised or lightly pressurised fuselageportion.

EP 0 847 916 B1 accordingly discloses a pressure frame in the shape of adome, in particular at the tail-end termination of the pressurisedregion of an aircraft fuselage, an annular frame being provided toreceive annular forces in particular, the annular frame being formed bythe edge of the dome, in such a way that the edge having a transitionregion having the internal radius of curvature is turned up at an acuteangle in the direction of the fuselage tail in such a way that it fitstightly against the inside of the fuselage structure in a peripheralcontact strip having a predetermined width.

DE 39 23 871 C2 also discloses a pressure frame made of fibre compositematerial for an aircraft having a pressure fuselage, the pressure framecomprising a dome shape which transitions at the edge into a shapecorresponding to the aircraft. In the edge region the pressure frame isreinforced by the integration of further fibre layers, and rigid fibrematerial can preferably be used here.

In an aircraft having a pressure frame, it is necessary to pass lines,in particular fuel lines, from the pressurised region of the fuselageinto the pressure-free region and vice versa, and in this case maintainthe prevailing pressure difference between the fuselage regions. Forexample, a fuel line must be passed from a central wing box of theaircraft to an auxiliary energy unit, such as an auxiliary gas turbine,which is normally arranged in the tail region of the aircraft, or totail-end trimming tanks of the aircraft. To do this, it is necessary topass the fuel line through the pressure frame arranged at the tail end.It is operatively known to the applicant to pass the fuel line throughthe pressure frame by means of a suitable arrangement for passing thefuel line through. The pressure frame comprises an opening for thispurpose, in which a sleeve is arranged which is sealed against theopening by means of an O-ring. The fuel line is passed through thesleeve and is sealed against the sleeve by means of a further O-ring. Anaxial displacement of the line and a rotation of the line relative tothe pressure frame are therefore possible. It has however proveddisadvantageous that, owing to the lack of mechanical decoupling of theline from the pressure frame in the case of deformations of the pressureframe or the surrounding fuselage structure, an unacceptably highmechanical loading of the fuel line is reached, as a result of which,for example, leakages in a line system of the aircraft can occur. Thisis obviously to be avoided.

SUMMARY OF THE INVENTION

It is therefore one idea of the present invention to provide an improvedarrangement for passing a line in a load-free manner through a pressureframe of a fuselage of an aircraft or spacecraft, which arrangementeliminates the above-mentioned disadvantages.

An arrangement is accordingly provided for passing a line in a load-freemanner through a pressure frame of a fuselage of an aircraft orspacecraft, comprising: an opening penetrating the pressure frame,through which opening the line is passed, the line being mechanicallydecoupled from the pressure frame; and a flexible sealing devicearranged outside the opening, at least in portions, which device issimultaneously operatively connected to the line and the pressure framefor pressure-tight separation of a first side from a second side of thepressure frame.

A fuselage for an aircraft or spacecraft having an arrangement of thistype and an aircraft or spacecraft having an arrangement of this type orhaving a fuselage of this type are also provided.

The idea on which the present invention is based consists in providingan arrangement which allows the line to be passed through the pressureframe in such a way that the line is mechanically decoupled from thepressure frame. It is hereby possible to reliably prevent mechanicalloading of the line, even in the case of severe deformation and/ordeformation of varying severity of the fuselage structure and/or of thepressure frame owing to flight loads and/or loads resulting from thepressurisation of the pressure frame. The occurrence of leakages in aline system of an aircraft or spacecraft can thus be prevented by anarrangement of this type, as a result of which the reliability of anaircraft of this type is increased.

According to a preferred embodiment, the sealing device is formed in onepiece. This ensures a particularly simple, economical andeasy-to-assemble construction of the arrangement.

According to a preferred embodiment, a predetermined air gap is arrangedbetween an edge of the opening and the line in order to achieve freemovability of the line in the opening. Axial and radial movability ofthe line in the opening is hereby advantageously ensured, as a result ofwhich the line is mechanically decoupled from the pressure frame at alltimes.

According to a further preferred embodiment, the sealing device isconstructed as a bellows. The sealing device can thus be deformedparticularly easily and without transmitting forces to the line.

According to a further preferred embodiment, the sealing device isarranged on the first side of the pressure frame. There is preferably ahigher pressure on the first side of the pressure frame than on thesecond side of the pressure frame. There is thus an overpressure on theoutside of the sealing device at all times, as a result of which anexcessive expansion of the sealing device and possible damage thereto asa result is reliably prevented.

According to a further preferred embodiment, the sealing device hasapproximately a truncated cone shape having a first end-face flangeportion and a second end-face flange portion, the sealing device inparticular tapering, starting from the second end-face flange portion,towards the first end-face flange portion. A cross-sectional differencefrom the opening towards the line can hereby advantageously be bridgedwithout the use of additional construction elements.

According to a further preferred embodiment, the line comprises a firstcoupling device assigned to the first, in particular pressurised, sideof the pressure frame, and a second coupling device assigned to thesecond, in particular unpressurised, side of the pressure frame. Amodular construction of a line system of the aircraft or spacecraft ishereby advantageously ensured, as a result of which individualcomponents of the line system can be conveniently replaced.

According to a further preferred embodiment, the first coupling deviceis fixed to a first structural element of the fuselage, which structuralelement is assigned to the first side of the pressure frame, and asecond coupling device is fixed to the second structural elementassigned to the second side of the pressure frame. A reliablepositioning of the line relative to the pressure frame is herebyensured. The line thus moves together with the load-bearing structuralelements of the fuselage.

According to a further preferred embodiment, the sealing device is fixedto the first coupling device of the line, as a result of which theassembly effort required to assemble the sealing device is reduced.

According to a further preferred embodiment, the arrangement comprises aflange which surrounds the opening, extends out from the pressure frameand is in particular tubular. A simple and convenient assembly of thesealing device is hereby ensured, the device being operatively connectedonly to the projecting flange for assembly on the pressure frame.

According to a further preferred embodiment, the flange extends out fromthe pressure frame on the first side thereof, as a result of which theflange is advantageously only minimally deformed in the case of abending deformation of the pressure frame.

According to a further preferred embodiment, the sealing device is fixedto an end portion of the flange. A simple assembly of the sealing deviceby sliding the sealing device onto the end portion is hereby ensured.

According to a further preferred embodiment, the line is formed as afuel line, as a result of which the arrangement advantageously ensures aleakage-free fuel supply of an aircraft or spacecraft having anarrangement of this type.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention is described in further detail in the following by way ofembodiments with reference to the appended schematic figures of thedrawings.

In the figures:

FIG. 1 is a sectional view of a preferred embodiment of an arrangementfor passing a line in a load-free manner through a pressure frame of afuselage of an aircraft or spacecraft;

FIG. 2 is a perspective view of the arrangement according to FIGS. 1;and

FIG. 3 is a further perspective view of the arrangement according toFIG. 1.

In the figures, like reference numerals denote like or functionallyequivalent components, unless stated otherwise.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1 to 3, which are referred to simultaneously in the following,illustrate a preferred embodiment of an arrangement 1 for passing a line2 in a load-free manner through a pressure frame 3 of a fuselage 4, inparticular a fuselage airframe 4, of an aircraft or spacecraft 5. Thefuselage 4 is preferably formed using a fibre-reinforced plasticsmaterial, in particular using a carbon-fibre-reinforced plasticsmaterial. The fuselage 4 can comprise a metal material. This materialcan be flexibly deformed by mechanical loads which act on the fuselage 4during operation of the aircraft or spacecraft 5. A longitudinaldirection of the fuselage 4 is denoted by x, a transverse direction by yand a vertical direction by z.

The line 2 is preferably formed as a fuel line 2 of the aircraft orspacecraft 5. The line 2 can also be formed as an electrical ormechanical supply line 2. The line 2 is in particular formed as adouble-walled line 2 having an inner wall 6 and an outer wall 7 whichconcentrically surrounds the inner wall 6. The inner wall 6 preferablyhas a tubular cross-section through which fuel is conveyed. Anintermediate space 8, in particular an intermediate space 8 filled withair, is provided between the inner wall 6 and the outer wall 7. Theintermediate space 8 can be filled with a gas other than air, forexample with an inert gas. The intermediate space 8 can also bedrainable. The walls 6, 7 can be formed using a fibre-reinforcedplastics material and/or a metal material. The line 2 preferablycomprises a first end-face coupling device 9 and a second end-facecoupling device 10. The line 2 is operatively connected to a line system31 of the aircraft or spacecraft 5 in a detachable manner by means ofthe coupling devices 9, 10. The coupling devices 9, 10 are for exampleformed as detachable quick couplings 9, 10.

The pressure frame 3, also referred to as a pressure dome 3 or pressurebulkhead 3, preferably divides an interior 32 of the fuselage 4 in thex-direction into at least a first fuselage portion 11 and a secondfuselage portion 12. The first fuselage portion 11 is for example formedas a passenger cabin 11 of the aircraft or spacecraft 5. The secondfuselage portion 12 can be an unpressurised region 12 of the aircraft orspacecraft 5. A first side 13 of the pressure frame 3 preferably facestowards the first fuselage portion 11 and a second side 14 of thepressure frame 3 preferably faces towards the second fuselage portion12. The pressure frame 3 is preferably curved convexly towards thesecond side 14. When viewed from the second fuselage portion 12, thepressure frame 3 is in particular curved convexly into said fuselageportion. The pressure frame 3 preferably has an approximatelywatch-glass shape. Air pressure, in particular artificially produced airpressure, is preferably applied to the first fuselage portion 11 and thefirst side 13 of the pressure dome. The second fuselage portion 12 andthe second side 14 of the pressure frame 3 are preferably unpressurised,that is to say an artificially produced overpressure preferably does notprevail in the second fuselage portion 12. The second fuselage portion12 is for example under atmospheric pressure. An air-pressure differencepreferably prevails between the first side 13 and the second side 14 ofthe pressure frame 3. The pressure frame 3 is preferably peripherallyoperatively connected to the fuselage 4 or to load-bearing structures ofthe fuselage 4. For this purpose, the pressure frame 3 can comprise aperipheral annular frame which is connected to the fuselage 4. Thepressure frame 3 can be formed integrally with the fuselage 4, inparticular with a fuselage skin. For example, the pressure frame 3 isformed using a fibre-reinforced plastics material, in particular acarbon-fibre-reinforced plastics material. The pressure frame 3 cancomprise a metal material, such as an aluminium material. The pressureframe 3 absorbs loads resulting from the pressurisation of the firstfuselage portion 11 and flight loads occurring during operation of theaircraft or spacecraft 5. The pressure frame 3 can hereby be flexiblydeformed.

The pressure frame 3 further comprises an opening 15 penetratingtherethrough and comprising an edge 16, in particular a peripheral edge.The opening 15 is preferably circular. Alternatively, the opening 15 canfor example be rectangular or elliptical. The opening 15 connects thefuselage portions 11, 12 to one another. The line 2 is passed throughthe opening 15. The line 2 is preferably mechanically decoupled from thepressure frame 3 in this case. In particular, the line 2 is passedthrough the opening 15 without contact therewith. In order to achievefree movability of the line 2 in the opening 15, a predetermined air gap17 is arranged between the line 2 and the edge 16 of the opening 15. Theline 2 can move in the opening 15, preferably in the x-, y- and/orx-direction. The air gap 17 preferably completely surrounds the line 2and ensures at all times that the line 2 is mechanically decoupled fromthe pressure frame 3. A thickness d of the air gap 17, which ispreferably measured starting from the outer wall 7 to the edge 16, isformed in such a way that the line 2 does not contact the edge 16 evenin the case of severe deformations and/or deformations of varyingseverity of the fuselage 4 and/or the pressure bulkhead 3, as a resultof which mechanical decoupling of the line 2 from the pressure frame 3is ensured at all times.

The line 2 is preferably fixed to a structural element 18 of thefuselage 4 using the first coupling device 9, which is in particularassigned to the first side 13 of the pressure frame 3. A fixing element34 which operatively connects the structural element 18 and the couplingdevice 9 can be provided for this purpose. The structural element 18 isfor example a crossbar 18 of the fuselage 4. The second coupling device10 of the line 2, which is preferably assigned to the second side 14 ofthe pressure frame 3, is preferably fixed to a further structuralelement 19. The further structural element 19 is for example a so-calledA-bracket 19 of the fuselage 4. An A-bracket is a bracket connected toload-bearing elements of the fuselage 4. The line 2 is thus mounted onthe two structural elements 18, 19 and passed through the pressure frame3 by means of the opening 15. The line 2 is thus preferably decoupledfrom movements and/or deformations of the pressure frame 3. The line 2can be mounted on the structural elements 18, 19 or on one of thestructural elements 18, 19 in the form of a movable mounting, that is tosay, for example, so as to be displaceable in the x-direction.

The arrangement 1 preferably comprises a sealing device 20, which is inparticular flexible, is arranged outside the opening 15 at least inportions and is preferably simultaneously operatively connected to theline 2 and to the pressure frame 3 for the pressure-tight separation ofthe first side 13 from the second side 14 of the pressure frame 3. Thesealing device 20 preferably separates the fuselage portions 11, 12 fromone another in a pressure-tight manner. The sealing device 20 is inparticular formed in one piece. The sealing device 20 is preferablyformed using a rubber-elastic material, such as a rubber material and/orsilicone material. The sealing device 20 can be fibre-reinforced and/orformed as fibrous tissue. For example, the sealing device 20 is formedas a bellows 20. The sealing device 20 is preferably arranged on thefirst side 13, that is to say on the pressurised side 13, of thepressure frame 3. The sealing device 20 preferably projects into thefirst fuselage portion 11. In particular, the sealing device 20 allowsthe line to move in the opening 15 in an x-, y-, and/or z-direction. Inthe case of a displacement of the line 2 in the x-direction relative tothe pressure frame 3, the sealing device 20 can be displaced in theopening 15, at least in part. This allows the greatest possible axialdisplaceability of the line 2 in the x-direction relative to thepressure frame 3. The preferably flexible configuration of the sealingdevice 2 also ensures movability of the line 2 relative to the edge 16of the opening 15 in the y- and z-directions at all times.

The sealing device 20 preferably has approximately a truncated coneshape comprising a first end-face flange portion 21 and a secondend-face flange portion 22. The sealing device 20 preferably tapersstarting from the second end-face flange portion 22 towards the firstend-face flange portion 21. The sealing device 20 is preferably fixed tothe first coupling device 9 of the line 2. In particular, the firstend-face flange portion 21 of the sealing device 20 is fixed to thefirst coupling device 9 and/or the first structural element 18 by meansof two clamps 23, 24, arranged with axial spacing from one another. Theflange portion 21 preferably surrounds the line 2 and/or the couplingdevice 9 in such a way that a pressure-tight operative connection isproduced therebetween. The second end-face flange portion 22 of thesealing device 20 is preferably operatively connected to the pressureframe 3.

The arrangement 1 comprises in particular a preferably tubular flange 25which surrounds the opening 15 and extends out from the pressure frame3. The flange 25 extends for example from the first side 13 of thepressure frame 3 towards the first fuselage portion 11 and has inparticular a leading edge which is oriented approximately parallel tothe z-direction. The flange 25 is preferably formed as an A-bracket 25.The flange 25 in particular comprises a contact portion 26 whichpreferably rests on the surface of the pressure frame 3 in a planarmanner. The contact portion 26 can rest on the first side 13 of thepressure frame 3. The contact portion 26 is preferably connected to thepressure frame 3, for example by means of a rivet connection whichcomprises a large number of rivets 33. The contact portion 26 canalternatively or additionally be screwed, glued or connected in any wayto the pressure frame 3. A seal can be provided between the contactportion 26 and the pressure frame 3. Alternatively, the contact portion26 can be formed integrally with the pressure frame 3. A centre axis 27of the flange 25 extends preferably approximately parallel to thex-direction. The sealing device 20 is preferably fixed to an end portion28 of the flange 20. The second end-face flange portion 22 of thesealing device 20 is preferably mounted on the end portion 28 of theflange 25 by means of two clamps 29, 30. The flange portion 22 of thesealing device 20 can be glued to the end portion 28. The end portion 28can have a peripheral protrusion on the outside, which protrusion isoperatively engaged with the flange portion 22 in order to fix thisflange portion in the x-direction. The flange portion 22 preferablysurrounds the end portion 28 of the flange 25 in such a way that apressure-tight connection is produced therebetween.

By means of the arrangement 1 it is possible to pass the line 2, whichis fixed to corresponding structural elements 18, 19 of the fuselage 4by means of the coupling devices 9, 10, in a load-free manner throughthe opening 15 of the pressure frame. In this case, the line 2 ismechanically decoupled from the pressure frame 3 at all times, as aresult of which no unwanted loads are transferred to the line 2.Mechanical loading of the coupling devices 9, 10 is thus prevented, as aresult of which the danger of a leak occurring in the line system 31 ofthe aircraft or spacecraft is avoided or at least reduced.

The materials, numerical data and dimensions given are to be understoodas examples and merely serve to illustrate the embodiments anddevelopments of the present invention.

It is obviously also possible to use the invention in other fields, inparticular in vehicle construction or shipbuilding.

What is claimed is:
 1. An arrangement for passing a line in a load-freemanner through a pressure frame of a fuselage of an aircraft orspacecraft, comprising: an opening penetrating the pressure frame,through which opening the line is passed, wherein the line ismechanically decoupled from the pressure frame; and a flexible sealingdevice arranged outside the opening at least in portions, which sealingdevice is simultaneously operatively connected to the line and thepressure frame for the pressure-tight separation of a first side from asecond side of the pressure frame.
 2. The arrangement according to claim1, wherein the sealing device is formed in one piece.
 3. The arrangementaccording to claim 1, wherein a predetermined air gap is arrangedbetween the line and an edge of the opening in order to achieve freemovability of the line in the opening.
 4. The arrangement according toclaim 1, wherein the sealing device is formed as a bellows.
 5. Thearrangement according to claim 1, wherein the sealing device is arrangedon the first side of the pressure frame.
 6. The arrangement according toclaim 1, wherein the sealing device has approximately a truncated coneshape having a first end-face flange portion and a second end-faceflange portion, the sealing device in particular tapering, starting fromthe second end-face flange portion, towards the first end-face flangeportion.
 7. The arrangement according to claim 1, wherein the linecomprises a first coupling device assigned to the first, in particularpressurised, side of the pressure frame, and a second coupling deviceassigned to the second, in particular unpressurised, side of thepressure frame.
 8. The arrangement according to claim 7, wherein thefirst coupling device is fixed to a first structural element of thefuselage, which structural element is assigned to the first side of thepressure frame, and the second coupling device is fixed to a secondstructural element assigned to the second side of the pressure frame. 9.The arrangement according to claim 7, wherein the sealing device isfixed to the first coupling device of the line.
 10. The arrangementaccording to claim 1, wherein the arrangement comprises a flange whichsurrounds the opening, extends out from the pressure frame
 11. Thearrangement according to claim 10, wherein the flange is tubular. 12.The arrangement according to claim 10, wherein the flange extends outfrom the pressure frame on the first side thereof.
 13. The arrangementaccording to claim 10, wherein the sealing device is fixed to an endportion of the flange.
 14. The arrangement according to claim 1, whereinthe line is formed as a fuel line.
 15. A fuselage for an aircraft orspacecraft having an arrangement according to claim
 1. 16. An aircraftor spacecraft having an arrangement according to claim 1.